I will see where I wrote category B instead of class B. It is simply a
typo. Thanks for catching that.

I am certainly up for a better explanation of how GPS works. Indeed my
information comes from the common espousals.

I understand the concept of RAIM prediction, that the GPS can predict the
unavailability of RAIM. However, I was not aware that RAIM had the ability
to predict as oppose to detect positioning errors.

I would appreciate further information on either basic GPS or RAIM.

John Bell


"Ron Natalie" wrote in message
m...

"John Bell" wrote in message
om...

Other hypothesis are also welcome.

Class B airspace, not category B.

Your simplified definition of GPS, while one of the common ones often
espoused
has no basis in reality. This is not how GPS works.

Your information on RAIM is wrong. What is unique about the RAIM used in
IFR
approved GPS's is not that it determines when the satellite geometry is
giving you
an error NOW, but computes if it will fail while during the expected
duration of flying
an instrument approach.